Flashcards in Congenital Heart Defects Deck (14):
What is acyanosis?
Acyanotic defects are ones which do not result in a lower than normal concentration of oxygen in the blood.
What is an Atrial septal defect?
Atrial Septal Defects are openings in the atrial septum that continues after birth. Pressure in the left is higher than that of the right so blood flows from left to right so the defect is acyanotic.
What are the two types of ASD and which is most common?
Most commonly occurs at the foramen ovale – called Ostium Secundum ASD, Ostium Primmum ASD occurs at the inferior part of the septum and is much less common.
What is a patent foreman ovale?
PFO (patent foreman ovale) – foreman ovale doesn’t properly shut after birth. This is common in about 25% of people but in most there is not shunting as the flap is functionally closed by, unless large increase in pressure in the right atria such as coughing – paradoxical embolism. This does not come under the classification of an ASD.
What is a ventricular septal defect?
Ventricular Septal Defects are openings in the ventricular septum resulting in left to right movement of blood so acyanotic. Most commonly occurs in membranous portion of the septum but can take place anywhere along it.
What is a patent ductus Arteriosus
PDA (Patent Ductus Arteriosus) – ductus arteriosus is still slightly open - Acyonotic. Produces a continuous heart murmur throughout systole and diastole.
Describe the haemodynamic effects of ASD and VSD.
Haemodynamic effects of ASD and VSD are to: increase pulmonary blood flow, RV overload and eventual right hear failure.
What is Eisenmenger's Syndorme
Chronic left to right shunting can lead to vascular remodelling of pulmonary circulation and increase in pulmonary resistance. If this resistance > systemic circulation this could cause the shunting to change direction – known as Eisenmenger Syndrome.
Describe Coarctation of the Aorta.
Narrowing of the aorta just after the ligamentum arteriosum, narrowing increases the afterload on the left ventricle and may lead to left ventricle hypertrophy. Upper part of the body will receive normal blood supply (may be hypertensive) however the rest of the body will have reduced flow. Baby will be born with symptoms of heart failure.
What is cyanosis?
Cyanotic Defects are ones where there is mixing of deoxygenated blood with oxygenated blood.
Describe the 4 defects that result in Tetralogy of Fallout.
Tetralogy of Fallouta occurs due to a single developmental defect placing the outflow portion of the interventricular septum too far in the anterior and cephalad directions: VSD, Overriding Aorta (aorta positioned over VSD), Pulmonary Stenosis (narrowing), Right ventricular Hypertrophy. The Stenosis causes the ventricular hypertrophy so much so that the force of blood pumping becomes harder than that of the left ventricle and so blood flows through the VSD and is taken up by the aorta leading to cyanotic effects.
Explain why Tricupsid atresia is incompatible with life without certain other complications.
Tricuspid Atresia is a lack of the tricuspid valve. The only way this can be present in a live birth is if there is also a complete ASD or PFO right to left shunt and a VSD or PDA to allow blood to flow through the pulmonary circulation.
Explain why transposition of the great arteries is incompatible with life without inducing other complications.
Transposition of the Great Arteries results in two unconnected circulations forming because the septum that forms in the truncus arteriosus does not spiral. The left ventricle is connected to the pulmonary trunk and the right ventricle to the aorta. Not compatible with life unless the ductus arteriosus can be left open and or an atrial septal defect is formed to allow time for the baby to be taken into theatre for surgery.